The analysis is as follows:

1, the red exclamation mark is on, indicating that the brakes are out of order, or the brake pads need to be replaced and are not in braking state.

2, the brake pedal stroke is too large, the braking effect is slow, the braking efficiency is very low or even lost, and the braking distance is increased.

3. Reasons for failure

(1) Insufficient brake oil pressure.

(2) There is air in the braking system.

(3) The free travel of the brake pedal or the brake clearance is too large, and the friction plate of the brake shoe has poor contact, serious wear or oil pollution.

(4) The brake master cylinder, wheel cylinder piston and cylinder tube are worn or deformed, and the cups are aged and damaged.

Extended data

Judgment and elimination of faults

1. Keep pressing the brake pedal. If the pedal rises gradually, it feels elastic, but it is still low when pedaling after a short pause, indicating that there is air in the braking system. At this point, the braking system should be ventilated.

2. One-foot braking is invalid, but stepping on the pedal several times in a row has a good braking effect, generally because the free stroke of the brake pedal is too large or the braking clearance is too large. Adjust the free travel of the pedal, then check the brake clearance, and if necessary, remove and repair the brake.

3. When stepping on the brake pedal, the strength is not too big, but the braking effect is poor. This phenomenon is the failure of wheel braking, such as oil pollution or poor contact of brake shoes, aging and wear of friction plates and uneven wear of brake drums. Check the technical condition of the brake, and make adjustments and repairs if necessary.

Baidu Encyclopedia: Brake System